Some believe this tree to be more than 1,500 years old.

The ill-fated plan to reroute the Mississippi so that Union ships could bypass Confederate fortifications on the river bend.

Yup, that's where the name came from.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

Look closely and you’ll notice that the color changes a third of the way up the tower.

A heroic pigeon that, through a barrage of gunfire, delivered a message that saved over 100 lives in World War I.

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.

The 28,000-year-old specimen is remarkably intact.

One day a year it is legal to jump off of this astoundingly tall bridge that spans an Appalachian gorge.

The world's tallest statue of an American hero.

Legend has it the commander of the defenders drew a fateful line in the dirt with his sword just before the final battle.

Two small markers remember the Alamo's feline protectors.

During the solar phenomenon "Lahaina Noon" this bendy, curvy sculpture forms a perfectly circular shadow on the ground.

The largest protected conservation area in the Ozarks—a region that stretches into northern Arkansas and southern Missouri.

The granite monument is engraved with the image of the talking horse's head coming through a barn door.

The "lovely red Vega" of the legendary record-settling pilot.

The fountains of the U.S. Navy Memorial are annually salted with water from the Seven Seas as part of a nautical ritual.

A taste of Middle Earth, in the middle of the Bayou City.

An acoustic anomaly with a mysterious cause sits in the heart of Tulsa.

This legendary city has been a tourist attraction for centuries.

This 15th-century island fortress later served as home to the executioners no one wanted to live near.

The second largest surviving chained library is housed in this 12th century church.

Fascinating town where normal life interfaces with the occult.

Cliffs full of fossils at the portal to England's Jurassic Coast.